I found this offer on WH Smith, and if you like books it seems a good deal. Free delivery and 8% Quidco too.

3 For 2 On All Books1. For a limited time WHSmith are offering 3 for the price of 2 on ALL Books 2. Valid until 7am Monday 14th July 2008 3. Subject to availability 4. To qualify for the offer, all books must be purchased in the same transaction, the lowest priced item will show as £0.00 in your basket 5. If you do not purchase enough products to qualify for this offer, you will be charged at the normal price 6. Valid on all books that have a 13 digit ISBN number and are listed in our Books area 7. Excludes book products offer through our partner sites (eg Personalised books, personalised Ordnance Survey Maps) 8. Offer valid online only